check squirrelsquid ships's afterburners. there are two ways you can make it: one is like a flow of fire. this one looks nicer, but ain't much credible(and practic). the other, more simple, is just to draw a "ball" behind it that dissapears in a simple 2frame animation like the Cerberus. in both cases, the output trail of fire will always be proportional to the ships's mass. or else, you'll get this odd tail appearance.
I didn't mean that you had to copy it. its a reference ok? now it just looks like a fox tail. plus the cycle isn't working, ruining the animation's smoothness. go and check other references mkay?
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